Old logs are not imported into ES by logstash

Question

When I start logstash, the old logs are not imported into ES.
Only the new request logs are recorded in ES.
Now I\'ve see this in the doc.

Even if I set the

Answer 1

Please see this line also.

This option only modifies "first contact" situations where a file is new and not seen before. If a file has already been seen before, this option has no effect.